Carlos Baleba is believed to have a sell-on clause embedded in his current contract which could end up stinging Manchester United . The Red Devils have made their interest in the Brighton & Hove Albion star known this summer, despite the Seagulls insisting that their talented midfielder isn't for sale. As a result, the 21-year-old has seen a price tag of around £100million slapped on his head, with United chiefs reportedly conceding that a move ahead of September 1 is highly unlikely. However, future endeavours to tie the Cameroonian down to a contract at Old Trafford could be hindered by a sell-on clause, as reported by Fabrizio Romano. Baleba is claimed to have a stipulation in his current deal which means that 15 per cent of any sale from Brighton will go to Lille. As per reports, Brighton agreed the clause with the Ligue 1 outfit when the two clubs struck a deal of around £26m two years ago. It could help explain Brighton's hefty valuation of Baleba and their firm stance in talks over a sale. The Seagulls have a figure in mind they want to receive to allow the youngster to leave the Amex Stadium, given a portion of it will go to his former club. Theoretically, United could have been looking at an £85m asking price for Baleba if there was no contract clause, as Brighton wouldn't be losing £15m of their £100m valuation to Lille in that scenario. Ruben Amorim is coming to the end of his maiden summer transfer window at Old Trafford, and he has spent big on new recruits over the past couple of months. More than £200m has been splashed on the likes of Matheus Cunha , Bryan Mbeumo and Benjamin Sesko . However, the Portuguese tactician could have been in a better position to negotiate for Baleba should he have been able to permanently shift some of the players who are not a part of his plans. Sales will undoubtedly put the Red Devils in a better position with regards to the pressures of PSR, and while there's still hope that a deal can be found to move on Alejandro Garnacho , given that Chelsea are said to be closing in on a deal for the winger, other surplus assets like Rasmus Hojlund , Jadon Sancho and Antony appear to be at a standstill. United have managed to save around £12million in wages after Marcus Rashford committed to a year-long loan move to Barcelona with an option to buy, although the club were hopeful of finding a permanent home for the academy product, who fell out of favour with Amorim. Meanwhile, Hojlund's future has been cast into doubt given the arrival of Sesko from RB Leipzig in a £73.7m move earlier this month. Despite being linked with loan moves to the likes of Napoli and AC Milan, the Dane is insistent on staying in the north west to fight for his place during the new campaign. Amorim failed to find success with his ageing midfield made up of Casemiro and Christian Eriksen last term, but it's not just the centre of the park which could do with strengthening ahead of deadline day. Andre Onana has failed to live up to his own £47.2m price tag since arriving from Inter Milan in 2023, making a number of costly mistakes in the English top flight despite arriving as one of the world's brightest shot stoppers. As the Cameroonian has only just recovered from a hamstring injury, Altay Bayindir was deployed as Amorim's choice of keeper during United's Premier League opener against Arsenal at Old Trafford on Sunday. Following United's 1-0 loss, it remains to be seen as to whether United will make a last-ditch attempt to find a new No. 1 ahead of the window shutting on September 1.